megapixels vs sensor size

The sensor size chart- Megapixels versus sensor size
While you can get a 16MP camera for little money, it does not mean you just got a camera that can make quality photos. In fact, a camera with less megapixels and a larger sensor will give you a better result.
The sensor size chart below will help you determine the sizes of sensors for commonly used camera types.

If we compare the sensor size with the megapixel count we get the following sensor size chart:

Pixel count

Sensor size

3.3 million

5.3 x 4.0 mm

5.0 million

7.2 x 5.3 mm

8.0 million

8.8 x 6.6 mm

8.0 million

8.8 x 6.6 mm

8.0 million

8.8 x 6.6 mm

8.0 million

8.8 x 6.6 mm

6.1 million

23.7 x 15.7 mm

12.2 million

23.7 x 15.7 mm

13.8 million

36 x 24 mm

16.6 million

36 x 24 mm

If you look at the numbers that a commonly used camera uses, you can notice that a larger pixel count will require a larger sensor. This in turn increases the cost not only of the camera drastically, but also requires a larger lens!
Naturally, you can get a cheapie camera with a large number of pixels, but this will not help you make professional photos. A large sensor will.
Since these cheaper cameras do sport the same pixel counts as the larger cameras, the megapixels versus sensor size ratio will be needed to actually determine if you are actually buying a camera that can leverage the pixel count. So a camera with a larger sensor and a smaller MP count will be better that the camera with a smaller sensor and more pixels.
In conclusion
Ever since the pocket camera versions started appearing with large pixel counts, it has been hard to gauge the quality of a camera just by the pixels. The solution to this has been to make use of other information, primarily the size of the camera sensor.
The sensor size chart above gives you an idea about the industry averages when it comes to sensor sizes and megapixels. Generally, a pixel range lower than the listed sensor size is not optimal. A good balance of both is needed.